.list {
  margin: 20px auto;
  width: 350px;
  height: 200px;
  border: 1px solid #000;
  overflow-y: auto; 
}

.item {
  box-sizing: border-box;
  padding: 0 20px;
  height: 40px;
  line-height: 40px;
  border-bottom: 1px solid yellowgreen;
}